/*******************************************************************************
 * Copyright (c) 2004, 2005 Elias Volanakis and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Elias Volanakis - initial API and implementation
 *******************************************************************************/
package edu.ccut.saturn.studio.logic.model.commands;

import org.eclipse.gef.commands.Command;

import edu.ccut.saturn.studio.logic.model.Connection;
import edu.ccut.saturn.studio.logic.model.Shape;
import edu.ccut.saturn.studio.logic.model.saturn.SaturnDecisionNode;
/**
 * A command to disconnect (remove) a connection from its endpoints. The command
 * can be undone or redone.
 * 
 * @author Elias Volanakis
 */
public class ConnectionDeleteCommand extends Command {

	private static final String CONNECTION_DELETE_BLANK = "";
	private static final String CONNECTION_DELETION = "connection deletion";
	/** Connection instance to disconnect. */
	private final Connection connection;

	/**
	 * Create a command that will disconnect a connection from its endpoints.
	 * 
	 * @param conn
	 *            the connection instance to disconnect (non-null)
	 * @throws IllegalArgumentException
	 *             if conn is null
	 */
	public ConnectionDeleteCommand(Connection conn) {
		if (conn == null) {
			throw new IllegalArgumentException();
		}
		setLabel(CONNECTION_DELETION);
		this.connection = conn;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.gef.commands.Command#execute()
	 */
	public void execute() {
		connection.disconnect();
		Shape source = connection.getSource();
		if ((source instanceof SaturnDecisionNode)
				&& (this.connection.getLineStyle() == Connection.SOLID_CONNECTION)) {
			((SaturnDecisionNode) source).setThenid(CONNECTION_DELETE_BLANK);

		} else if ((source instanceof SaturnDecisionNode)
				&& (this.connection.getLineStyle() == Connection.DASHED_CONNECTION)) {
			((SaturnDecisionNode) source).setFalseId(CONNECTION_DELETE_BLANK);
		} else {
//			source.setNextId(CONNECTION_DELETE_BLANK);
		}
		source.modifyShape();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.gef.commands.Command#undo()
	 */
	public void undo() {
		connection.reconnect();
	}
}
